Polarization-dependent interference in nonlinear Compton scattering

We investigate the phase interference effects in the nonlinear Compton scattering via the collision between a high-energy electron and the laser in the intermediate intensity region, and reveal that the importance of interference effects on the scattered photons depends sensitively on the relative polarization of the scattered photons and laser pulse. For scattered photons polarized parallel to the laser field, the effective distance between two interfered phase points is much larger than that for perpendicularly polarized photons. To signalize the phase interference effect in potential experiments, we introduce the double-pulse scenario for the scattering process, and show that the interference between two phase-separated pulses could significantly modulate the energy-momentum distribution of the scattered photons, leading to the reshaping of the scattered photons’ energy spectrum. By narrowing the angular acceptance of the scattered photons, the spectral modulation can be amplified and sustained for an experiment-realizable phase separation between two pulses.